The Scala Future API

The Scala Future and Promise API is defined in the scala.concurrent package. This API is used to develop concurrent and parallel applications in the Scala language.

The Future represents a computation unit; this unit is executed by Promise and put into the Future.

In simple words, Future is an object to read that result and Promise is an object to execute that computation unit. Let's explore these concepts in depth, with some useful examples in the coming sections.

Building blocks of the Scala Future API

The Scala Future API has the following building blocks:

• Scala Future
• Scala Promise
• Scala ExecutionContext

The following diagram shows the main building blocks of the Scala Future API:

These are...